Ravens have attacked and killed six new calves by pecking out their eyes on two Chatsworth Township farms this year – a recent phenomenon for many in this rural area where the number one livestock predator is the coyote.

Five of the attacks have been on calves owned by Steve Stewart, who farms south of Owen Sound, near Williamsford. Township farmer Robert Thompson also lost a Charolais calf that way this year.

Grey County saw the most reported injuries and deaths by ravens on livestock from April to December last year, figures from the Ontario Ministry of Agriculture and Rural Affairs show. Eight of 11 calf deaths were reported in Grey County, one in Bruce County and the rest in Simcoe and Renfrew counties.

Province-wide in that period there were 43 sheep deaths and injuries -- none in Grey County -- as the result of these clever black birds which stand 30 to 45 centimetres high, whose population is growing in Ontario.

The number of raven kills has been increasing since 2011, when two calves and four sheep were killed or injured across the province, said Richard Horne, manager of policy and issues with the Beef Farmers of Ontario.

That could be because livestock examiners may be getting better at identifying raven attacks now, he said. Raven kills only represent about 1% of the total livestock deaths province-wide, he noted. Coyotes are number one.

But the number of ravens in the area is growing, Chatsworth Mayor Bob Pringle said. They're a protected species and have been nesting in abandoned barns, he said. They've begun to be a problem for farmers in the last few years but ravens in Western Canada have been a problem years, he said.

So far this year more calves have been killed by ravens than coyotes in Chatsworth, said Brian Klages, one of the township's livestock examiners. The problem has only been around for about five years.

“The government says it's against the law to shoot them, the ravens,” he said. But prices for two -or three-day-old calves run around $1,100 to $1,200, so it's a big expense. He typically has found young, healthy calves with their eyes missing but otherwise left alone. Ravens attack calfs up to a week old, he said.

He noted bounties are paid for coyotes and 40 have been shot in the Desboro and Keady area alone last year.

But in that Alfred Hitchcock thriller, the birds started turning on people.

One picture of a calf remains shows a blood-stained calf's head missing one of its eyes but otherwise the animal remains intact. Moore said one of Stewart's calves had its eyes pecked out and “rear-end eaten out,” though another scavenger could have been responsible for that.

“The little calves are either laying down (or) sleeping,” Moore said. “They'll swarm them and start pecking the eyes out.”

In each case, a livestock evaluator has inspected the dead animal and photographed it to confirm the death and identify its cause. Pecked out eyes are a telltale sign of a raven attack.

The pictures and the evaluator's report are forwarded by the municipality to the province's Ontario Wildlife Damage Compensation Program. It reimburses the township at the market rate for calves. Ravens are among 17 recognized predators of livestock and poultry for which compensation is paid.

Farmer Steve Stewart, who lost five calves this season, said Friday he was too busy haying to talk about it. “I haven't witnessed an attack but we've been having problems. They've kind of wrecked our barn and other damage as well as calves. They're getting to be a bit of a problem alright.”

Roy and Anna May Enever lost seven or eight calves before compensation became available in 2011. “We were going over and finding these newborn calves and we thought they're dead, what the devil is going on,” Anna May said.

Eventually they discovered a calf with a bleeding eye and took it to a veterinarian who was familiar with the raven problem. A woman at the vet heard that discussion and said the birds attacked her sheep.

Roy Enever is another livestock examiner in Chatsworth Township. He said once newborns settle on the ground, they won't get up until their mothers return. The birds wait for the animals to blink and the deed is done, he said.

He started getting calls about ravens killing newborn livestock in the past few years. Like Klages, he's heard of more calf deaths due to ravens than coyotes so far this year in the township.

The Enevers moved their calving to a barn on their main farm to be closer and haven't had the same problem since.

When they were losing calves, just two ravens were in the barn. Later 30 or 40 roosted, ripped up insulation and fouled the feed. The Enevers shot one, strung it up, having heard that keeps the rest away and that seemed to help, she said. She understands that's allowed when livestock are under attack.

The raven population has increased in Ontario and is expanding its range southward, a Ministry of Natural Resources and Forestry spokeswoman said by e-mail. The breeding bird atlas shows they were found in a handful of new places in Grey County in the most recent survey period, 2001-2005. They naturally nest on cliffs or in large cavity trees but have learned to take advantage of communication towers for nesting, she said.